The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Modern vehicles may employ a fuel supply system and more specifically, a fuel pump module such as that depicted in FIG. 1. Such a fuel pump module may employ a return fuel line 2 that returns unused fuel from an internal combustion engine to a fuel reservoir 4 at the same time that fuel is delivered from a fuel tank to the engine. As part of an overall fuel supply system, a vacuum is created in a fuel supply line 6 by a fuel injection pump, which may draw fuel from reservoir 4 to deliver such fuel to the engine. Fuel that is unused by the engine may be returned to fuel reservoir 4 and pass through a transfer jet pump 8 and a reservoir jet pump 10, both residing within fuel reservoir 4. As depicted, no fuel pump is present within reservoir 4, which may reside within a vehicle fuel tank.
FIG. 2 depicts another arrangement of components within fuel reservoir 4 in accordance with the prior art. More specifically, fuel reservoir 4 may employ fuel supply line 6 to supply fuel to an engine while return fuel line 2 may deliver unused fuel from the engine directly to fuel reservoir 4, without passing through any jet pumps. However, reservoir 4 of FIG. 2 also contains and employs an electric fuel pump 12 to pump liquid fuel into transfer jet pump 8 and reservoir jet pump 10. When electric fuel pump 12 is employed within reservoir 4, as depicted in FIG. 2, return fuel line 2 has no connection to a transfer jet pump 8 or reservoir jet pump 10, but instead an electric fuel pump 12 is directly connected to transfer jet pump 8 and reservoir jet pump 10 to permit just pumps 8, 10 to properly function. However, the structures of FIGS. 1 and 2, and their functionality, are not without their share of limitations. For instance, FIG. 1 depicts an arrangement in which fuel flow volume and pressure within return fuel line 2 must be sufficient enough at all times to invoke proper function of transfer jet pump 8 and reservoir jet pump 10 and may only be used in applications in which an engine fuel injection pump can adequately deliver an excess fuel flow of sufficient flow volume and pressure to operate transfer jet pump 8 and reservoir jet pump 10. During periods of excessive engine fuel demand, such a flow and pressure may be insufficient and starve transfer jet pump 8 and reservoir jet pump 10 of fuel, thus provoking a decrease in levels of fuel in reservoir 4. FIG. 2 depicts an arrangement in which electric fuel pump 12 is necessary to provide sufficient flow volume and flow pressure to transfer jet pump 8 and reservoir jet pump 10. Electric fuel pump 12 must operate at all times that the engine operates, thus decreasing pump longevity and increasing electrical consumption from a vehicle alternator or battery.
While arrangement of components within fuel reservoir 4, as depicted in FIGS. 1 and 2, has been satisfactory for their different purposes, a need exists for a single fuel delivery module and fuel delivery system that is capable of being used in all fuel delivery systems, regardless of fuel consumption by the engine, but that also conserves electrical energy consumed by a module fuel pump.